[Form 4] Black Rock Coffee Bar, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Cynosure-managed investment entities significantly increased their stake in Black Rock Coffee Bar, Inc. through open-market purchases and related equity structuring. On May 15, 2026, the reporting entities bought 1,600,000 shares of Class A Common Stock and 12,042,712 shares of Class B Common Stock at $5.35 per share in open-market or private transactions, all held indirectly.

They also converted 119,892 LLC Units into the same number of Class A shares on a 1-to-1 basis, with a corresponding 119,892 Class B shares cancelled for no consideration as part of this conversion. Following these transactions, Cynosure-affiliated funds collectively hold large positions in both Class A and Class B shares, with The Cynosure Group, LLC retaining sole voting and investment power over these holdings while each reporting person disclaims beneficial ownership of securities held directly by the others except for their pecuniary interest.

Insights

Equity ownership & governance analyst

Large Cynosure-led purchases increase economic exposure and clarify Up-C style structure.

The reporting entities associated with The Cynosure Group, LLC executed sizeable open-market purchases of both Class A and Class B Common Stock at $5.35 per share, alongside a conversion of LLC Units into Class A shares with matching Class B share cancellation.

This pattern is typical of an Up-C structure: LLC Units are redeemable into Class A stock on a 1-to-1 basis, while an equal number of Class B shares is forfeited. The filing states LLC Units have no expiration and can be redeemed at the holder’s option, so similar exchanges may occur over time as holders adjust their mix of voting and economic interests.

The transaction data and footnotes show The Cynosure Group, LLC has sole voting and investment power over these positions, with each fund disclaiming beneficial ownership of others’ holdings except for pecuniary interests. The net-buy profile suggests increased economic commitment, but the filing does not provide broader valuation or performance context, so the overall investment thesis impact remains neutral based solely on this information.

Insider Trade Summary

Net Buyer: 25,685,424 shares ($72,988,509)

Net Buy 6 txns

Insider Cynosure Group, LLC, Cynosure Partners 2020, LP, Cynosure Partners 2020 PV, LP, Cynosure Partners 2020 Co-investment, LLC, Cynosure Partners III, LP, Cynosure Partners III Offshore, LP

Role null | null | null | null | null | null

Bought 25,685,424 shs ($72.99M)

Type	Security	Shares	Price	Value
Purchase	LLC Units	12,042,712	$0.00	--
Conversion	LLC Units	119,892	$0.00	--
Purchase	Class B Common Stock	12,042,712	$5.35	$64.43M
Purchase	Class A Common Stock	1,600,000	$5.35	$8.56M
Other	Class B Common Stock	119,892	$0.00	--
Conversion	Class A Common Stock	119,892	$0.00	--

Holdings After Transaction: LLC Units — 19,915,304 shares (Indirect, See footnote); Class B Common Stock — 19,915,304 shares (Indirect, See footnote); Class A Common Stock — 1,916,012 shares (Indirect, See footnote)

Footnotes (1)

1. Consists of (i) 3,514,041 shares of Class B Common Stock held by Cynosure Partners 2020, LP, (ii) 260,660 shares of Class B Common Stock held by Cynosure Partners 2020 PV, LP, (iii) 660,106 shares of Class B Common Stock held by Cynosure Partners 2020 Co-Investment, LLC (for and on behalf Series A members), (iv) 1,247,093 shares of Class B Common Stock held by Cynosure Partners 2020 Co-Investment, LLC (for and on behalf Series B members), and (v) 14,233,404 shares (or 14,113,512 shares, after giving effect to the transaction described in (3) below) of Class B Common Stock held by Cynosure Partners III, LP. The Cynosure Group, LLC, is the manager for, and has sole voting and investment power with respect to, the shares of Class B Common Stock held by each of these entities. Each of the Reporting Persons disclaims beneficial ownership of the securities of the Issuer held directly by any of the other Reporting Persons except to the extent of their pecuniary interest therein. Consists of (i) 1,916,012 shares of Class A Common Stock held by Cynosure Partners III Offshore, LP and, after giving effect to the transaction described in (4) below, (ii) 119,892 shares of Class A Common Stock held by Cynosure Partners III, LP. The Cynosure Group, LLC, is the manager for, and has sole voting and investment power with respect to, the shares of Class A Common Stock held by each of these entities. Each of the Reporting Persons disclaims beneficial ownership of the securities of the Issuer held directly by any of the other Reporting Persons except to the extent of their pecuniary interest therein. Reflects the cancellation for no consideration of Class B Common Stock in connection with the conversion of LLC Units. Reflects the conversion of 119,892 LLC Units into Class A Common Stock on a 1-to-1 basis. The LLC Units may be redeemed by the Reporting Person at any time at the option of the holder for shares of Class A Common Stock on a 1-to-1 basis, and a corresponding number of shares of Class B Common Stock will be forfeited in connection with the redemption. The LLC Units have no expiration date.

Key Figures

Class A shares purchased: 1,600,000 shares Class B shares purchased: 12,042,712 shares LLC Units converted: 119,892 LLC Units +5 more

8 metrics

Class A shares purchased 1,600,000 shares Class A Common Stock bought at $5.35 on May 15, 2026

Class B shares purchased 12,042,712 shares Class B Common Stock bought at $5.35 on May 15, 2026

LLC Units converted 119,892 LLC Units Converted into 119,892 Class A shares on a 1-to-1 basis

Class B shares cancelled 119,892 shares Class B Common Stock cancelled for no consideration upon LLC Unit conversion

Post-transaction Class B holdings 19,915,304 shares Class B Common Stock held across Cynosure funds after purchases

Post-transaction Class A structure 2,035,904 shares Class A Common Stock held by Cynosure Partners III LP and Offshore LP combined

Purchase price $5.35 per share Price for Class A and Class B open-market or private purchases

Net buy shares 25,685,424 shares Net buy direction across all reported transactions

Key Terms

Class A Common Stock, Class B Common Stock, LLC Units, Conversion of derivative security, +1 more

5 terms

Class A Common Stock financial

"1,600,000 shares of Class A Common Stock purchased at $5.35 per share"

Class A common stock is a category of a company’s shares that carries a specific set of ownership rights—most commonly defined voting power and claims on dividends—set out in the company’s charter. For investors it matters because the class determines how much influence you have over corporate decisions, the share’s likely dividend and trading behavior, and how it compares in value to other share classes, like choosing a particular seat with different privileges at the company’s decision-making table.

Class B Common Stock financial

"12,042,712 shares of Class B Common Stock purchased at $5.35 per share"

A class B common stock is one of multiple types of a company’s ordinary shares that carries specific rights—often different voting power or dividend priority—compared with other classes. For investors it matters because those differences affect how much influence you have over company decisions, the income you might receive, and how freely the shares trade; think of it like owning a car with different keys: some keys let you start the engine and open the trunk, others only unlock the door.

LLC Units financial

"conversion of 119,892 LLC Units into Class A Common Stock on a 1-to-1 basis"

LLC units are ownership stakes in a limited liability company, similar to shares in a corporation; each unit represents a portion of the company’s profits, losses and often voting power. For investors, LLC units matter because they determine how much money and control someone gets, how easily an interest can be sold, and how income is taxed and reported — think of owning slices of a pie that also decide how the pie is cut and shared.

Conversion of derivative security financial

"transaction code C is described as Conversion of derivative security"

open-market purchase financial

"transaction code P is described as Purchase in open market or private transaction"

An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Cynosure Group, LLC

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Black Rock Coffee Bar, Inc. [ BRCB ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/15/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Class B Common Stock	05/15/2026		P		12,042,712	A	$5.35	19,915,304	I	See footnote(1)
Class A Common Stock	05/15/2026		P		1,600,000	A	$5.35	1,916,012	I	See footnote(2)
Class B Common Stock	05/15/2026		J		119,892	D	(3)	19,795,412	I	See footnote(1)
Class A Common Stock	05/15/2026		C		119,892	A	(4)	2,035,904	I	See footnote(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
LLC Units	(5)	05/15/2026		P		12,042,712		(5)	(5)	Class A Common Stock	12,042,712	(5)	19,915,304	I	See footnote(1)
LLC Units	(5)	05/15/2026		C			119,892	(4)	(4)	Class A Common Stock	119,892	(4)	19,795,412	I	See footnote(2)

1. Name and Address of Reporting Person^*

Cynosure Group, LLC

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Cynosure Partners 2020, LP

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Cynosure Partners 2020 PV, LP

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Cynosure Partners 2020 Co-investment, LLC

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Cynosure Partners III, LP

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Cynosure Partners III Offshore, LP

(Last) (First) (Middle)

111 S. MAIN STREET, SUITE 2350

(Street)

SALT LAKE CITY UTAH 84111

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

Explanation of Responses:

1. Consists of (i) 3,514,041 shares of Class B Common Stock held by Cynosure Partners 2020, LP, (ii) 260,660 shares of Class B Common Stock held by Cynosure Partners 2020 PV, LP, (iii) 660,106 shares of Class B Common Stock held by Cynosure Partners 2020 Co-Investment, LLC (for and on behalf Series A members), (iv) 1,247,093 shares of Class B Common Stock held by Cynosure Partners 2020 Co-Investment, LLC (for and on behalf Series B members), and (v) 14,233,404 shares (or 14,113,512 shares, after giving effect to the transaction described in (3) below) of Class B Common Stock held by Cynosure Partners III, LP. The Cynosure Group, LLC, is the manager for, and has sole voting and investment power with respect to, the shares of Class B Common Stock held by each of these entities. Each of the Reporting Persons disclaims beneficial ownership of the securities of the Issuer held directly by any of the other Reporting Persons except to the extent of their pecuniary interest therein.

2. Consists of (i) 1,916,012 shares of Class A Common Stock held by Cynosure Partners III Offshore, LP and, after giving effect to the transaction described in (4) below, (ii) 119,892 shares of Class A Common Stock held by Cynosure Partners III, LP. The Cynosure Group, LLC, is the manager for, and has sole voting and investment power with respect to, the shares of Class A Common Stock held by each of these entities. Each of the Reporting Persons disclaims beneficial ownership of the securities of the Issuer held directly by any of the other Reporting Persons except to the extent of their pecuniary interest therein.

3. Reflects the cancellation for no consideration of Class B Common Stock in connection with the conversion of LLC Units.

4. Reflects the conversion of 119,892 LLC Units into Class A Common Stock on a 1-to-1 basis.

5. The LLC Units may be redeemed by the Reporting Person at any time at the option of the holder for shares of Class A Common Stock on a 1-to-1 basis, and a corresponding number of shares of Class B Common Stock will be forfeited in connection with the redemption. The LLC Units have no expiration date.

Remarks:

Each of the Reporting Persons may be deemed to be a director-by-deputization of the Issuer solely for purposes of Section 16 of the Securities Exchange Act of 1934 by virtue of The Cynosure Group, LLC's current right to nominate an individual to serve on the board of directors of the Issuer (the "Board"), and under which Andrew Braithwaite, a Managing Director of The Cynosure Group, LLC, serves on the Board.

	/s/ Andrew Braithwaite, Authorized Signatory	05/19/2026
	/s/ Andrew Braithwaite, Authorized Signatory	05/19/2026
	/s/ Andrew Braithwaite, Authorized Signatory	05/19/2026
	/s/ Andrew Braithwaite, Authorized Signatory	05/19/2026
	/s/ Andrew Braithwaite, Authorized Signatory	05/19/2026
	/s/ Andrew Braithwaite, Authorized Signatory	05/19/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)